1. Field of the Invention
The present invention relates in general to a device for automatically controlling vehicle lighting systems, and, more particularly, to a universally applicable device for automatically turning on all of a vehicle's exterior lighting and related equipment upon activation of the vehicle's windshield wiper motor; and turning off said lighting and related equipment upon turning off the vehicle's ignition, or upon deactivation by the vehicle's operator; further to provide means for turning on the vehicle's exterior lighting and related equipment upon turning on the vehicle's ignition, or upon manual activation by the vehicle's operator, and turning off said lighting and related equipment upon turning off the vehicle's ignition, or upon manual deactivation by the vehicle's operator.
2. Prior Art
It has long been recognized that turning on vehicle headlights during reduced visibility conditions in the daytime helps reduce accidents. In a growing number of states and in some foreign countries, law requires use of headlights in such conditions. But while such measures enhance safety, they have the unfortunate side effect of draining batteries when vehicle operators forget to turn the lights off when they leave their vehicles. This presents vehicle operators and law enforcement personnel with a dilemma. As long as there is concern about forgetting to turn their lights off, some operators will leave them off, and risk traffic violations rather than dead batteries.
Reduced visibility specified in such laws includes bad weather conditions, when windshield wipers can be expected to be in use, but also includes situations in which headlight use is required or desired, but windshield wiper use is not, such as smoky or foggy conditions. In addition, many vehicle operators who begin a trip before sunrise and arrive at their destinations in daylight, fail to turn their lights off upon arrival. The operator should be encouraged to use the headlights in such circumstances, assured that they will not be unintentionally left on.
There is a growing need for a universal device which will control headlight systems on all vehicles in all such situations. To be universal in application and acceptance, its design should reflect the fact that responsibility for operating a vehicle rests with its operator, which responsibility should not be usurped. The device should feel natural in use, reducing rather than increasing the operator's burden. It should be adaptable to any vehicle without replacing, modifying, or interfering with the vehicle's original equipment or functions, and it should operate the same way on all vehicles so operators are not confused by it when driving different vehicles. To gain the widest possible acceptance, it should be simple to install.
To meet these requirements, the device should turn the headlights on automatically only when there is a high degree of certainty that headlight use is required or desirable. In the present case, this requirement is met a) when the windshield wiper motor begins to operate, since it is reasonable to assume that the weather conditions requiring wiper use include those in which headlight use is required or desirable, or b) when the operator elects to activate the headlights.
The same principle applies, and for safe operation is more critical, for turning the headlights off. The device should only turn the headlights off when there is a high degree of certainty that they are no longer needed or wanted. This requirement is met in the present case a) when the vehicle's ignition switch is turned off, since it can be reasonably assumed that the operator is discontinuing use of the vehicle when the ignition is turned off, or b) when the operator elects to deactivate the headlights.
There will be times when the vehicle's operator would reasonably choose to override the automatic controls provided by the device. The device must allow the operator to exercise this responsibility.
The need for a control device to operate headlights automatically is pointed out in U.S. Pat. Nos. 3,824,405; 4,010,380; 4,097,839; 4,337,400; 4,656,363; 4,831,310; 4,956,562; 4,985,660; and 5,027,001.
The Glaze U.S. Pat. No. 3,824,405 discloses a device with a modified windshield wiper control switch. It requires replacement of the vehicle's original equipment. On the numerous vehicles with the wiper switch positioned between the wiper motor and ground, the voltage required to trigger the device's relay is not present, and the device will not function properly. It also will not function properly on vehicles with interval wiper systems.
The Bailer et al. U.S. Pat. No. 4,010,380 shows a combined light and windshield wiper switch. It requires replacement of the vehicle's original headlight and wiper switching equipment, and in use would cause increased current flow through the ignition switch. On many vehicles, extensive rewiring would be required to safely accommodate the device.
The Lesiak U.S. Pat. No. 4,097,839 discloses a relay-activated switching device which is not universal because it assumes a directly-grounded wiper motor. On vehicles equipped with the wiper switch between the motor and ground, and there are many, the device would not function properly. On such systems, if the relay were attached on the battery side of the motor, it would be always on. If attached on the ground side of the motor, it would be always off.
The Hahn U.S. Pat. No. 4,337,400 shows a double pole single throw relay activated by a voltage drop across the ignition switch and wiper motor switch. On vehicles equipped with the wiper switch between the wiper motor and ground, the device would not function properly. On many vehicles with interval wiper systems, this device would flash the lights on and off with each pass of the wiper blades, which is undesirable and would shorten headlight life.
The Carter et al. U.S. Pat. No. 4,656,363 shows a device which also assumes a directly-grounded wiper motor. The device would not function properly on vehicles equipped with the wiper switch between the motor and ground. On such systems, if the device were attached on the battery side of the motor, it would be always on. If attached on the ground side of the motor, it would be always off.
The Heintzberger at al. U.S. Pat. No. 4,831,310 discloses a device which uses an AC signal generated when the vehicle's engine is running to determine when to activate the headlight system. This device is not related to activation of the windshield wipers. It has the undesirable effect of turning the lights off whenever the engine stops, which could be unintentional, due to stalling, fuel starvation or any other unintended cause.
The Benedict et al. U.S. Pat. No. 4,956,562 shows a device which operates on the basis of a positive voltage input from the wiper switch. On vehicles with the wiper switch between the wiper motor and ground, wiper switch closure brings the switch to ground, the required positive voltage would not be present with the wiper on, and the device would not operate properly.
The Cronk U.S. Pat. No. 4,985,660 discloses a device which is not universal in that it also assumes a directly-grounded wiper motor. On systems where the wiper switch is between the wiper motor and ground, the required voltage is not available to operate the device's relay, and the device will not function properly. It also has undesirable limitations in that it operates only the headlight low beams and not the high beams, tail lights or other lights and related equipment.
The Torbert U.S. Pat. No. 5,027,001 shows a device for activating a vehicle's wipers and headlights upon sensing of moisture on a vehicle's windshield. This device includes a separate control device which supersedes the vehicle's original wiper motor speed control equipment. It also allows a dangerous situation in which the headlights can unintentionally turn off at night when the headlights had been previously activated by the device in the daytime.
Whatever the merits, features and advantages of the above cited references, none of them achieves or fulfills the purposes of the present invention.